Caesium in Europe after Chernobyl
Many measurements have allowed the mapping of the caesium-137 ground activity after the accident. This activity is expressed in kilobecquerels (kBq) per square meter. These deposits added to the residues of the fallout from nuclear tests in the 50's and 60'S. The map shows contaminations nearly 1000 times higher near Chernobyl than in Western Europe because of the effects of distance. Altogether, Chernobyl deposits represent approximately three times the residual activity of nuclear tests in 1986.
IRSN